Wireframing. What is it and when should it be used?
Wireframing is used to layout web pages before coding them. The motivation is that it is much easier to change a wireframe (using Viso or Omnigraffle) then it is to change a HTML page or even (gulp!) a finished web site. Wireframing is not necessary for all sites but it is very helpful in realizing workflows (like a multi-step registration) and can save hours of time in subsequent phases of planning and development.